CLASS III.--Those monsters joined by a fusion of some of the cranial bones are sometimes called craniopagi. A very ancient observation of this kind is cited by Geoffroy-Saint-Hilaire. These two girls were born in 1495, and lived to be ten years old. They were normal in every respect, except that they were joined at the forehead, causing them to stand face to face and belly to belly. When one walked forward, the other was compelled to walk backward; their noses almost touched, and their eyes were directed laterally. At the death of one an attempt to separate the other from the cadaver was made, but it was unsuccessful, the second soon dying; the operation necessitated opening the cranium and parting the meninges. Bateman said that in 1501 there was living an instance of double female twins, joined at the forehead. This case was said to have been caused in the following manner: Two women, one of whom was pregnant with the twins at the time, were engaged in an earnest conversation, when a third, coming up behind them, knocked their heads together with a sharp blow. Bateman describes the death of one of the twins and its excision from the other, who died subsequently, evidently of septic infection. There is a possibility that this is merely a duplication of the account of the preceding case with a slight anachronism as to the time of death. At a foundling hospital in St. Petersburg there were born two living girls, in good health, joined by the heads. They were so united that the nose of one, if prolonged, would strike the ear of the other; they had perfectly independent existences, but their vascular systems had evident connection. Through extra mobility of their necks they could really lie in a straight line, one sleeping on the side and the other on the back. There is a report a of two girls joined at their vertices, who survived their birth. With the exception of this junction they were well formed and independent in existence. There was no communication of the cranial cavities, but simply fusion of the cranial bones covered by superficial fascia and skin. Daubenton has seen a case of union at the occiput, but further details are not quoted.